The present disclosure relates to a hollow fiber membrane module including a hollow fiber membrane bundle composed of plural hollow fiber membranes bundled together. In particular, the present disclosure relates to the structure of a housing case that houses the hollow fiber membrane bundle.
In the fields of semiconductor production, food industries and the like, hollow fiber membrane modules, in which hollow fiber membrane bundles composed of plural hollow fiber membranes bundled together are housed in housing cases (casings), are widely used for gas-liquid absorption, degasification, filtration and the like.
In many cases, the housing case is made of synthetic resin, metal or the like, and formed into a tubular shape, such as a cylinder, and a nozzle through which liquid to be processed or fluid after processing by a hollow fiber membrane bundle passes is provided in the vicinity of each end of the housing case. Further, caps, each including a tubular channel through which liquid to be processed or fluid after processing by the hollow fiber membrane bundle passes, are attached to both ends of the tubular housing case.
In the case that the caps are attached to both ends of the housing case as described above, it is necessary that the internal space of the housing case defined by the housing case and the caps is liquid-tightly sealed against the outside of the housing case.
For such seal, an O-ring is used in many cases. As specific structure in which this O-ring is arranged, conventionally, structure in which an O-ring is arranged between a flat surface formed on a cap and a flat surface formed on a housing case facing the flat surface of the cap in a parallel state is known. In this structure, when a cap is attached to the housing case, both of the cap and the housing case press the O-ring by their flat surfaces in contact with the O-ring, and a sealed state by the O-ring is achieved. International Patent Publication No. 2013/136903 (Patent Document 1) discloses an example of such seal structure.